Optimization study on neutron/γ radiation-protective clothing materials with computational human phantoms

Area of Science:

• Nuclear Science and Technology
• Radiation Protection
• Materials Science

Background:

• Nuclear science applications are expanding, necessitating robust radiation shielding for safety.
• Effective shielding is crucial for environmental protection and human health in nuclear technology.
• Current shielding materials require optimization for comprehensive neutron and gamma radiation protection.

Purpose of the Study:

• To design and evaluate novel composite radiation shielding materials.
• To assess the efficacy of ethylene-propylene diene monomer-based composites with boron carbide, gadolinium oxide, and tungsten.
• To quantify dose reduction for various organs and effective dose from neutron and gamma radiation.

Main Methods:

• Developed 20 composite shielding schemes with varying proportions of neutron absorbers (boron carbide, gadolinium oxide) and gamma shielding (tungsten).
• Utilized the Monte Carlo method with the Chinese Reference Adult Male (CRAM) voxel model and an anterior-posterior (AP) setup.
• Calculated organ/tissue doses and effective dose reductions for 1, 3, and 5 mm thicknesses, controlling errors within 1%.

Main Results:

• Optimal protection was achieved with 5 mm thickness for all composite materials.
• Effective dose reductions for neutron sources (252Cf and 1 keV) ranged from 32.60% to 69.42%.
• Gamma shielding (137Cs) resulted in effective dose reductions of 7.96% to 20.97%, showing dual-functionality.

Conclusions:

• Composite materials demonstrate significant potential for combined neutron and gamma radiation shielding.
• Consistent shielding performance across different neutron energies was observed.
• Full-body protection is recommended to address dose increases in partially exposed organs due to neutron scattering.